King and Mills attempted the first transcatheter closure of secundum ASD in 1976. Over the next three decades many different devices and techniques have been introduced. There are currently two such devices which are FDA approved in USA: The Amplatzer Septal Occluder (ASO) device which is a prosthesis that consists of two round nitinol wire disks connected together with a short connecting disk. It can be used in small, moderate and large ASDs. The second is the Helex Septal Occluder (HSO), which is a low profile device that has a double disk non-self-centering design. It has a built-in method for retrieval. It is used for small and moderate size ASDs.
Percutaneous ASD closure results not only in symptomatic improvement and increase in exercise capacity, but also in improvements in cardiac chamber geometry and in cardiac hemodynamics (). Majunke et al. studied 650 consecutive adults with median age of 45 who underwent closure with ASO. The patients had a mean PASP 33.3 mmHg. Implantation was successful in 98% of patients. Complete closure was achieved in 96% pts (22 of 25 of the incomplete closures had very small residual shunt). Mean PASP decreased to 28.3 mmHg. Intra-procedural complications consisted of 2 pts with device embolization, one pt with transient ST depression. 0.9% needed emergent CT surgery. The authors concluded that ASD closure in adults is safe, efficient with excellent long term outcome [7
]. Others have shown that ASD closure with an ASO device leads to significant decrease in RV size (right ventricular end diastolic diameter [RVEDD] 35.3 mm to 29.2 mm in first 24 hours) and improvement of clinical symptoms with an extremely high success rate (112 of 113). As such the authors suggest that ASD closure device should be the first option for management of secundum ASDs [8
]. Similar encouraging results have been reported in the Helex closure device. Jones et al. compared HSO to surgery at 12 month follow up and found that closure rate, major and minor adverse outcomes were the not different [9
]. Concern about potential development of mitral regurgitation was essentially put to rest when Wilson et al reported that a 2 year follow up of data in 227 adult and children post ASO showed 98.5% success for closure rate, resolution of AF in half of the patients post procedure and the degree of MR which was unchanged in 88% pts (In 1% MR increased by 2 grades and in 9% increase of 1 grade. 7% had decrease is MR) [10
Beneficial effects of percutaneous ASD closure in adults.
The comparison of surgical vs. percutaneous approach was reported in a large cohort of 596 pediatric patients in a non-randomized parallel group study. In this study, 442 patients received ASO device closure and 154 had surgical closure. Success rate was 95.7% in ASO and 100% in surgical group. There was no mortality observed in either group, however complication rate was significantly lower in the device group (7.2% ASO vs. 24.0% surgical). The length of stay was shorter in the transcatheter arm (1.0 vs. 3.4 days) [11
]. Similar rate of success (98%) with an increased length of stay (8 vs. 3 days) was observed by other studies [12
]. Five-year follow up data by Knepp et al. for ASO closure showed complete closure rate was 97% with very low incidence of mortality and morbidity [13
Given the success rate of closure devices and the lower complication rate, adult patients are more likely to select percutaneous approach for secundum ASD closure in order to avoid receiving a sternotomy and having to undergo cardiopulmonary bypass. From a public health standpoint, since the efficacy of both procedures are equal and the complications are generally lower in the percutaneous group there is a significant cost reduction benefit due to a shorter recovery and shorter hospital stay.